Arc-quenching material



Patented Dec. 30,1930

UNITED STATES- PATENT- OFFICE,

oonranrsrnnnor, or mywoon, mnmors, assrenoa 'ro ntucrnrcar. ENGINEERS nourrunn'r ea, or nnrnosn rm, ILLINOIS, A conrona'rrou or rumors ano-ounnonmo m rnnmr.

This invention relates to are quenching materials, especially those adapted for use in connection with high tensionapparatus and materials, as forinstance fuses, cables, entrance bushings, switches, and transformers;

' and to insuring positively a prompt quench-' ing of the arc when the fuse blows. -Heretofore a good deal of difliculty has been met in preventing and suppressing incipient arcs and consequent deterioration and ionization in cables; as also in controlling the flash and in extinguishingthe are or spark in high voltagev fuses, especially for large currents. These troubles relate both to the mechanical l5 securityof the apparatus, cable or fuse and also to the tendency of an unquenched arc to spread and cause extensive collateral damage, as by burning, ionization and-the like, besides failure of the fuse or other member to perform promptly its appropriate function. r

The main objects of this invention are to i provide animproved kind of arc quenching material; to provide such material in amorphous pasty or semi-solid form adapted for convenlent handling and use; to provide such afiller having great chemical stability underintense heat as against carbonizetion, oxidation or ionization to provide such an arcquenching material adapted to absorb or arrest the electrons liberated by the arc; to provide creep away from a heated body, such for instance as a fuse element when the latter gets 3 hot and so let the fuse bloyv; and to provide an im roved'kind or form of arc-quenching immo ate environment for the fuse wire it The filler material which I have discovered comprises a mixture of carbon tetrachloride, aluminum stearate and aluminum palmitate. The two latter materials are first mixed in about the proportion of seven to three in the order named, respectively, and then about 10% of this mixture is mixed with about 90% of the carbon tetrachloride, the resulting product being a gelatinous substance having. extremely high dielectric strength and other properties especially adapting it for are 6 quenching infuse cartridges Although the such a material which will recede or Application filed latch 19, 1928. semi iwda'eaase.

proportions above stated are well adapted for general purposes, it is practicable to vary these somewhat according to particular needs as may be found desirable,

Before these componentmaterials are mixed together, they have their own respective characteristics, The carbon tetrachloride is electrically and chemically a stable liquid, but physically, by itself alone, is very volatile at all ordinary temperatures. The

other two materials are meral soaps of a substantiallys'olid consistency. The carbon tetrachloride is rendered physically stable by mixing it with the soaps specified. The reason for using more stearate than pahnitate isfthat such a proportion results in a firmer elly. The roportion of this soap mixture may vary mm 3% to 15%, but if too much is used'the jelly is too stiff and the carbon tetrachloride is .less free to perform its aresmothering function. But if too little of said mixture is used, the jelly is toovsoft and yielding and will not creep away from the fuse element properly as the latter getshot, the fuse thus losing its dueresponsiveness. At the instant when the fuse blows, a volatilized fuse metal is scattered explosively through and is instantly chilled by the jelly which, being dielectric,insulates the various particles and, thereby at the same time quenches the arc and also precludes appreciable. ionization.

In operation, when the temperature reaches 100 to 150 C. the jelly shrinks away from the fuse wire, thus reducing its cooling action and permitting the fuse to respond promptly by blowing. 1

The use of this material in electric safety 7 cutouts is set forth in my divisional applicatipn, Serial No. 439,248, filed March'26, 1930.

The said jelly when used in transformers serves with great efliciency to quench any incipient arcmgand without any resultant carbonization such as occurs when oil is used. Moreover, the jelly serves as a good distributor for the heat enerated in a transformer and meets admirably all transformer requirements.

The jelly referred to when used to impregnate insulating paper in cables instantly quenches and suppresses any arcing or incipient tendencies to are and also prevents ionization.

This jelly is especially well adapted for use as a filler for high tension bus compartments, as will be understood.

Although a few specific uses of this invention are herein suggested, it is to be understood that no attempt has been made to mention specifically all of its practical uses.

I claim:

1. As an electric arc quenching material, a mixture of carbon tetrachloride, aluminum stearate and aluminum palmitate.

2. An electric arc quenching material comprising a mixture of from eighty-five per cent to ninety-seven per cent of carbon tetrachloride with a combination of aluminum stearate and aluminum palmitate.

3. An electric arc quenching material comprising a mixture of from eight-five per cent to ninety-seven per cent of carbon tetrachloride with a combination of aluminum stearate and aluminum palmitate, the two latter being mixed in the mutual ratio of about seven to three.

4. An electric arc quenching material in jelatinous form composed of liquid carbon tetrachloride and a mixture of naturally solid metallic soaps, the latter being capable of absorbing suflicient of said liquid to produce the consistency of jelly.

5. A conductor bedding material composed I of an arc quenching Volatile liquid and a metallic soap of naturally solid consistency, the latter being jellified by absorption of the former at ordinary temperatures and the liquid being volatile at temperatures occurring adjacent to fuse elements as the latter heat up under load.

6. As a dielectric material, a compound of carbon tetrachloride, eighty-five to ninetyseven percent, in combination with three to fifteen percent of a mixture of aluminum stearate and aluminum palmitate mutually proportioned at about seventy per cent of the former to thirty percent of the latter.

19 gsigned at Chicago this 14th day of March,

' GODFBEYSTEERUP. 

